Compressor



Oct. 11, 1966 J. H. HEIDORN 3,278,110

COMPRESSOR Original Filed July 15, 1959 4 Sheets-Sheet 1 Y L Q n Q Q John H. Heidarn I INVENTo Oct. 11, 1966 J. H. HEIDORN 3,278,110

COMPRES SOR Original Filed July l5, 1959 4 Sheets-Sheet 2 IN V EN TOR.

H15 A TTORNIE Y Oct. 11, 1966 J. H. HEIDORN COMPRESSOR Original Filed July l5 mmvron. Jahn H. Heidam HIS ATTORNEY Oct. 11, 1966 J. H. HEIDORN COMPRESSOR 4 Sheets-Sheet 4 Original Filed July 15 1959 United States Patent O 3,278,110 COMPRESSOR John I-I. Heidorn, Dayton, Ohio, assigner to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application July 25, 1961, Ser. No. 126,683, now Patent No. 3,190,419, dated June 22, 1965, which is a division of application Ser. No. 827,346, July 15, 1959, now Patent No. 3,092,307, dated June 4, 1963. Divided and this application Oct. 19, 1964, Ser. No. 404,753

3 Claims. (Cl. 230-15) This is a division of divisional application Serial No. 126,683, now Patent No. 3,190,419 issued June 22, 1965, filed Iuly 25, 1961, which is a division of Serial No. 827,- 346, led July 15, 1959, now Patent 3,092,307.

This invention relates to refrigerating apparatus and more particularly to a refrigerant compressor for use in automobile air conditioning systems and the like.

A large number of problems present themselves in designing refrigerant compressors of the type which are adapted to be driven by a car engine either continuously or intermittently through a clutch. These problems result from the fact that the compressor is required to operate throughout a very Wide speed range wherein the speed of the compressor bears no relationship to the refrigeration requirements. The problems are multiplied by the fact that the amount of space available for the compressor is very limited and all of the parts must be of lightweight `construction and arranged in a small casing.

It is an object of this invention to provide a compressor which is adapted to be driven from a car engine through an improved clutch arrangement.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention are clearly shown.

In the drawings:

FIGURE 1 is a vertical sectional View showing a preferred form of the invention.

FIGURE 2 is a sectional view taken substantially on line 2 2 of FIGURE 1 with parts broken away.

FIGURE 3 is a sectional view taken substantially on line 3 -3 of FIGURE 1 looking in the direction of the arrows FIGURE 4 is a fragmentary sectional view showing the relationship of the oil pump housing to the drive shaft of the compressor.

FIGURE 5 is a sectional view taken on line 5-5 of FIGURE l and looking in the direction of the arrows.

FIGURE 6 is a sectional view showing a modied type of compressor.

FIGURE 7 is a sectional view taken substantially on line 7-7 of FIGURE 6 and looking in the direction of the arrows.

FIGURE 8 is a fragmentary sectional view showing the clutch in the early stages of engagement.

FIGURE 9 is a view similar to FIGURE 8 but showing the clutch fully engaged.

Referring now to FIGURE 1 of the drawings wherein a preferred embodiment of the invention has been shown, reference numerals 10 and 12 designate complementary cup-shaped casing elements which serve to enclose a multiple cylinder compressor. These casing elements are made of sheet metal and have their open ends arranged in telescoping relationship, as best shown in FIGURE 1.

The compressor consists of a cylinder block 14 which is supported within the casing element 12 and which is prov-ided with four cylinder bores 16 which are symmetrically arranged about the main drive shaft 18. By

3,278,110 Patented Oct. 1l, 1966 ate within the bores 16 in accordance with conventional practice. These piston elements are driven by the Wobble plate assembly 22 through the usual connecting rods 24. The gas to be compressed enters through the usual suction line 28 which communicates with the low pressure suction chamber 30 formed in the cylinder head 32. The usual valve plate 34 is disposed between the cylinder head 32 and the cylinder block 14 and is provided with the usual series of inlet and outlet ports 36 and 38, respectively. The compressed gas leaves the compressor through the outlet passage 40.

As best shown in FIGURES 1 and 3 of the drawings, the outlet valve reed 42 is circular in shape and has its center portion clamped firmly to the valve plate 34 by means of a cap screw 44. The extent of opening of the reed valve 42 is limited by a rigid backup plate member 46. The valve plate 42 is provided with cutaway portions 48 which render it more flexible and in effect divide the reed into four lobes which are tied together at their outer periphery. The backup plate 46, as shown in FIGURE 3, is provided with lobes which overlie the outlet ports 38. By constructing the reed valve in the form of a single platelike element, the severity of the opening and closing movement of the valve plate is reduced since the compressed gas flowing out of the one outlet port at a given time tends to retard the closing movement of the next preceding valve port and also tends to initiate the opening movement of the next succeeding valve port.

The main drive shaft 18 is supported for rotation within the casing section 10 by means of a irst ball bearing assembly 50 rin which the inner ball race 51 is secured to the shaft 18 and the outer ball race 54 is carried by the end wall of the casing 10. This first ball bearing assembly serves to take up the end thrust resulting from the wobble plate pushing against the piston elements. A second ball bearing assembly 52 is provided as shown and serves to take up the belt load. This second ball bearing assembly is arranged directly in line with the belts 55 which drive the compressor pulley 56 secured to the outer ball race of the ball bearing assembly 52. It will be noted that the bearing sleeve member 54 which forms the outer ball race for the bearing assembly 50 also forms the inner ball races of the ball bearing assembly 52 and is, in effect, an extension of the stationary housing element 10. By virtue of this bearing arrangement, the ball bearings and the associated ball races stand up much longer in service than the prior art arrangements as the bearing assembly 52 takes the main belt load and the balls are always moving about in the races whenever the car engine operates.

The inner end of the drive shaft 18 is journaled in the cylinder block 14 in such a manner that slight misalignment between the casing sections 10 and 12 will not cause excessive strain or wear on the drive shaft 18. As best shown in FIGURES 1 and 4 of the drawings, the inner end of the drive shaft extends into a tapered opening (shown somewhat exaggerated in FIGURE 4) in a member 60 which is adapted to rotate with the shaft 18. As shown in FIGURE 2 of the drawings, the shaft 18 is provided with a flat portion 62 which cooperates with a ilat port-ion on the member 60 so that the member 60 rotates with the shaft 18 but due to the taper on the' inner surface of the member 60, the shaft 18 need not line up exactly with the opening in the member 60.

The one end of the member 60 is provided with an oil pumping chamber 64. The inner Walls of the oil pumping chamber 64 are provided with conventional gear teeth projections 66 which cooperate with conventional oil pumping gear 68 rotatably supported on a fixed pin 70. Thus, the gear element 68 is cooperation with the rotating member 60 serves to form a gear type oil pump which supplies oil under pressure to the various bearings requiring7 lubrication.

Referring now to FIGURE l of lthe drawings, the bottom portion of the compressor casing serves as an oil Sump and oil from Ithis sump is pumped upwardly through the oil passage 72 to the inlet side of the oil pump just described. The oil discharges from the pump into a chamber 74 which communicates with oil passage means 76 and 78 provided in the pin 70 and in the main shaft 18. The oil is then fed through the radial passage 79 to the wobble plate bearings.

A coil spring 80 serves to bias the member 60 to the left as viewed in FIGURE 1. However, if the speed of the compressor should become great enough so that the quantity of oil handled by the pump exceeds the amount of oil which can ow through the oil feed passage 78, the excessive oil pressure in the pumping chamber will cause the elements 60 and the oil pump gear 68 to move to the right, as viewed in FIGURE 1, so as to automatically unload the oil pump.

When no refrigeration is required, the compressor may be declutched from the car engine and the drive pulley 56 by means of the magnetic clutch shown in FIGURES 1 and 5. This clutch includes a solenoid 90 embedded in the pulley 56, as shown. Current is supplied to the solenoid 90 by means of a collector ring 92 cooperating with a brush element 94 carried by the fixed casing element 10. The solenoid coil 90 is adapted when energized to pull the armature element 96 into frictional engagement with the surface 98 provided on the pulley 56. The one side of the solenoid 90 is grounded to the pulley S6 and in order to insure proper electrical connection between the pulley assembly and the rest of the compressor, a spring pressed ground contact 91 is provided, as shown, for at all times making electrical connection between the housing 108 of the pulley assembly and the shaft 18.

When the armature 96 first contacts the surface 98 in response to energization of the solenoid 90, the armature 96 will tend to rotate with the pulley 56 with the result that a series of conventional spreader balls 100 will serve to force the clutch plate 102 to the right, as viewed in FIGURE 1, so that the friction material 104 carried by the clutch plate 102 will engage the clutch surface 106 formed on the clutch enclosing casing element 108. The element 108 is secured to the pulley 56 so as to rotate therewith. A plate element 110' which is keyed to the drive shaft 18 is arranged between the armature 96 and the clutch plate 102. This plate element is secured to the clutch plate 102 through a plurality of arcuate spring members 112, as best shown in FIGURE 5. One end of each of the spring -arms 112 is secured to the plate 110 by means of a rivet 114 and the other end of each of the spring arms is secured to the plate 102 by means of rivets 116.

A conventional oil seal assembly 120 is provided for preventing the escape of lubricant and refrigerant at the point where the drive shaft 18 passes through the end wall of the casing 10. Suitable O-ring seals 122 are provided, as lshown, for preventing the leakage of gas between various parts of the compressor elements.

In FIGURE 6 of the drawings, a modified form of the invention is shown. Like reference numbers have been used in FIGURES 1 and 6 to designate identical parts or parts which are similar in function. AIn the modification shown in FIGURE 6, a plain end thrust bearing 200 is provided for t-he drive shaft 18. The main drive pulley 202 is rotatably supported on the compressor housing by means of Ia ball bearing assembly 204 which is directly in line with the drive belts 55 so as to take up the belt load. The clutch for operating the compressor differs from the clutch construction described hereinabove in that in place of using a clutch of the type wherein the clutch surfaces are mechanically held in engagement and the solenoid is merely used to initiate the operation of the clutch, the arangement shown in FIGURE 6- utilizes a clutch of the type in which the solenoid coil 206 holds the clutch in engagement. In the arrangement shown, the solenoid coil 206 which corresponds to the solenoid of FIGURE 1 is arranged in a circular groove 208 formed in the outer face of the pulley 202. Suitable nonmagnetic material 210 serves to hold the solenoid 206 in place and also serves to support an armature ring 212 which is arranged as shown. Keyed to the shaft 18 is an armature supporting plate assembly 214- which is held in place on the shaft 18 by means of a nut 215. The plate assembly 214 carries a first ringlike armature element 216 and a second ringlike armature element 218. The armature supporting plate assembly comprises a rigid plate 230 carried by the shaft 18 and a flexible armature supporting plate 232 to which the armature rings 216 and 218 are secured by means of rivets 234. Armlike projections 236 formed on the plate 232 and having their extremities secured to the rigid plate 230 by means of rivets 238 enable the armature rings 216 and 218 to move into and out of engagement with the complementary clutch surfaces. The armature ring element 216 is slightly thicker than the element 218 with the result that when the solenoid 206 is first energized, the armature element 216 will move into contact with the surfaces 220l and 222 (see FIGURE 8) and at a subsequent time, the armature element 218 will move into frictional engagement with the surfaces 224 and 226, as shown in FIGURE 9. The advantage of the above described arrangement is that the pull exerted aga-inst the armature 218 serves `to increase the pressure between the element 216 and the surfaces 220 and 222.

The compressor and clutch are of the `general type disclosed in United States application Serial Number 496,131, filed March 23, 1955, now Patent Number 2,907,426, issued October 6, 1959, to 'which reference may be made for -a more detailed explanation of the principle of operation thereof.

While the embodiments of the present invention as herein disclosed, constitute preferred forms, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. In combination, a sheet metal casing, a compressor disposed within said casing, a drive shaft extending through one wall of said casing, a bearing sleeve carried by said casing, first bearing means carried by said sleeve rotatably supporting said drive shaft, pulley means having a portion surrounding the outer end of said drive shaft, and second bearing means carried by said sleeve rotatably supporting said pulley means on said sleeve, and clutch means for drivingly connecting said pulley means to said shaft.

2. In combination, a casing, a compressor disposed within said casing, a drive shaft extending through one wall of said casing, 4a bearing sleeve carried by said casing, first bearing means carried by said sleeve rotatably supporting said drive shaft, pulley means having a portion surrounding the outer end of said `drive shaft, and second bearing means carried by said sleeve rotatably supporting said pulley means on said sleeve, and clutch means for drivingly Iconnecting said pulley means to said shaft, said pulley means having a plurality of axially spaced clutch surfaces formed thereon, said clutch means comprising a pair of clutch plates and means for spreading said clutch plates so as to positively force said clutch plates into engagement with said spaced clutch surfaces.

3. In combination, a casing, a compressor disposed within said casing, a drive shaft extending through one wall of said casing, a bearing sleeve carried by said casing, first bearing means carried by said sleeve rotatably supporting said drive shaft, pulley means secured to the outer end of said drive shaft, and second 4bearing means carried by said sleeve rotatably supporting,r said pulley means on said sleeve, and clutch means for drivingly connecting said pulley means to said shaft, said pulley means having a plurality of axially spaced clutch surfaces formed thereon, said clutch means comprising a pair of clutch plates and means for spreading said clutch plates so as to positively force said clutch plates into engagement with said spaced clutch surfaces, said last named means including a solenoid coil carried by said pulley means for initiating operation of said spreading means.

References Cited by the Examiner UNITED STATES PATENTS 12/1958 Jacobs -192--35 9/1962 Pitts 192-84 

1. IN COMBINATION, A SHEET METAL CASING, A COMPRESSOR DISPOSED WITHIN SAID CASING, A DRIVE SHAFT EXTENDING THROUGH ONE WALL OF SAID CASING, A BEARING SLEEVE CARRIED BY SAID CASING, FIRST BEARING MEANS CARRIED BY SAID SLEEVE ROTATABLY SUPPORTING SAID DRIVE SHAFT, PULLEY MEANS HAVING A PORTION SURROUNDING THE OUTER END OF SAID DRIVE SHAFT, AND SECOND BEARING MEANS CARRIED BY SAID SLEEVE ROTATABLY SUPPORTING SAID PULLEY MEANS ON SAID SLEEVE, AND CLUTCH MEANS FOR DRIVINGLY CONNECTING SAID PULLEY MEANS TO SAID SHAFT. 